There are a host of intra-abdominal and intra-thoracic sites in which abscesses may occur. In certain endoscopic procedures, such as anterior resection of the rectum, complications may occur leading to anastomotic leakage, which in turn may lead to an abscess formation. Some studies have shown that anastomotic leakage after anterior resection of the rectum occurs anywhere from 4.5% to 18% of the time. Such problems are often aggravated by a physiologic obstruction in the anal region. Accumulation of gases and feces results in movement of this waste material through the path of least resistance, which in most cases, and especially in the case of anastomotic leakage, is out of the colonic lumen and into the abdominal cavity. The backflow into the abdominal cavity typically leads to a pressure build-up next to the anastomosis, which in turn leads to mechanical enlargement of the tissue at the anastomosis and formation of an abscess. Proper healing of the anastomosis is therefore continually impaired.
During healing, the materials that are utilized to reattach the tissues are in direct contact with intestinal contaminants. These contaminants may enter into the walls of the intestinal repair through this contact with the stool and other contaminants, depending upon the location of the repair. This contamination of the site may contribute to serious complications including delayed healing, increased risk of infection or tissue necrosis, and anastomosis repair leakage.
Negative pressure therapy has been utilized for the healing of open wounds and has been commercialized, for example, by Kinetic Concepts, Inc. of San Antonio, Tex., with its proprietary V.A.C.® product line. In practice, the application to a wound of negative gauge pressure, typically involves the mechanical-like contraction of the wound with simultaneous removal of excess fluid. In this manner, V.A.C.® therapy augments the body's natural inflammatory process while alleviating many of the known intrinsic side effects, such as the production of edema caused by increased blood flow absent the necessary vascular structure for proper venous return. As a result, V.A.C.® therapy has been shown to be highly successful in the promotion of wound closure, healing many wounds previously thought largely untreatable. However, treatment utilizing V.A.C.® therapy has been largely limited to open surface wounds. Treatment of internal wounds, such as internal abscesses, has typically involved more traditional techniques such as surgical excision, treatment with antibiotics, etc. Other more complicated internal conditions, such as anastomotic leakage, have been even more problematic to treat.
Little has been known about the best ways to treat such anastomotic leakage. Some standard procedures used for this indication include nasogastric suction, broad-spectrum antibiotics, and parenteral nutrition. Other surgical procedures have included drainage of the leakage, loop colostomy, resection of the anastomosis (known as the Hartmann's procedure to those skilled in the art), and abdominoperineal excision of the rectum with a terminal stoma.
Products have been developed to provide temporary barriers to contaminants through the application of sleeve-like products, such as COLOSHIELD®, which are placed within the lumen of the intestinal structure and are attached superior to the anastomosis though the use of surgical sutures, staples, hooks, etc. The product is essentially a hollow tubular barrier material that is long enough to bridge the anastomosis. The barrier material serves as a physical protection against any direct contact of contaminants with the underlying healing tissue. While this product may isolate the healing tissue from pressurization by direct contact with the intestinal contaminants, the device does not provide any extraction of fluids or contaminants from the wound site. Additionally, the fixation of the device requires the use of elements that penetrate the protective barrier and are fixed within the tissues. Contaminants may infiltrate the punctures created by any of the previously-mentioned attachment devices to fixate the product.
Others in the prior art have also attempted to address this problem. For example, US 2004/0093026 discloses a negative pressure wound care treatment system including a collecting subsystem having fluid channels, which also serves as a pressure distributor and that may be comprised of an open-cell, polyurethane foam having a pore size in the range of about 400 to 600 microns. The foam may be cut to a size corresponding to the geometry of an anastomotic leakage and its corresponding cavity, which may range from 7.0 cm in length and 3.0 cm in diameter to 0.5 cm×1.0 cm. Also disclosed is a system for placing the foam within the cavity. An evacuation tube comprises at least one port that communicates with the foam and is positioned at the distal end of the tube or on a side proximate to the distal end of the tube. The distal end of the evacuation tube is preferably placed in the middle of the foam. The foam may be fixed to the tube using a non-absorbable surgical suture. Alternatively, the foam may be welded or glued to the tube using techniques known to those skilled in the art. Other alternative embodiments disclosed include the use of biodegradable foam, in which case the foam is fixed to the evacuation tube using biodegradable means, such as bioabsorbable sutures. The opposing, or proximal, end of the tube is connected to a high-vacuum drainage system, into which effluent fluid may be collected. A subatmospheric pressure of up to 850 mbar is applied to the foam. The open-cell nature of the foam apparently provides equal distribution of the applied pressure to every surface of the cavity in contact with the foam, thus serving as a pressure distributor.
U.S. Pat. No. 4,641,653 discloses a device that provides a method and means for isolating the internal walls of hollow viscera or other body vessels from contact with materials, both fluids and solids, occurring naturally, ingested, or otherwise introduced into a body vessel. Isolation of a body vessel, according to the invention, is achieved by positioning and anchoring a sleeve, impervious to materials sought to be isolated within the vessel, in such a manner that the sleeve, at least adjacent its upstream end, is in sealing engagement with the surrounding interior tissue of the vessel. Material otherwise normally flowing into the vessel and being capable of interacting with the vessel to the detriment of the patient's health is thereby contained and rendered ineffectual or otherwise unaffected by the vessel. The device may be attached to a source of pressure to deploy the sleeve against the walls of the lumen to be protected. This device simply isolates the walls of the lumen from the contaminants, and does not actively evacuate materials from the surrounding tissues.
U.S. Pat. No. 7,211,114 discloses a device that is inserted into a patient's stomach endoscopically to separate ingested food from gastric fluids and, optionally, to separate ingested food in the duodenum from digestive enzymes. In one embodiment of the invention, a stent is inserted into a patient's gastrointestinal tract to bypass the stomach. The stent consists of a covered stent having one-way openings and/or valves on its annular surface and preferably at least one one-way valve at one end to permit entry of food and/or liquids. Optionally the one-way valve at the end of the stent can comprise a sleeve that extends through the stent, preferably into the duodenum or beyond. One end of the stent is intended to be positioned at or above the gastro-esophageal junction, and the other end is intended to be positioned in the duodenum or beyond. The net effect of endoscopic gastric bypass is to replicate some or all of the effects of a surgical gastric bypass. The device as disclosed provides a means by which to isolate the digestive secretions from the food, however, it does not disclose or contemplate protecting a surgical anatomosis.
Although devices and systems are available for various wound treatment and implantation and tissue isolation applications, there is a need in this art for an endoscopic wound care treatment system that is capable of effectively treating an internal organ or tissue abscess in a minimally invasive manner, and which is easily implanted.